The wind farm, which entered commercial operation earlier this month, is located near the central Montana community of Geyser. The Montana Public Service Commission (MPSC) approved placement of the $86.1 million project into the company's regulated rate base in February. Both the energy and associated renewable energy credits will be used to meet Montana's 15% by 2015 renewable portfolio standard.

Under the terms of the filing with the MPSC - which included a 10% authorized return on equity, a 5% estimated cost of debt and a capital structure of 52% debt and 48% equity - this project represents an approximate levelized price of $54/MWh for a 25-year period, which NorthWestern says is significantly less than the $69/MWh current qualifying facility rate for a project with similar attributes.